The present invention is generally related to wireless telephones, and more particularly to a radio frequency radiation shielding apparatus for wireless telephones.
Wireless telephones including, but not limited to cellular telephones, digital telephones, analog telephones, PCS telephones, and personal communication systems (the new generation of wireless communication products), generate radio frequency radiation, including an electromagnetic field (xe2x80x9cEMFxe2x80x9d), which may prove harmful to persons exposed to such radiation. In recent years, as the number of wireless phones has grown, so has the concern about tumors or other damage to the brain. Although the level of radiation emitted by such devices is relatively low, the antenna which emits the radiation is close to the head. There is also concern that such radiation can have a cumulative effect.
There is presently pending wireless phone legislation that would require retailers to offer protective devices whenever a wireless product is sold. Such legislation would also require manufacturers and retailers to provide warning information at the point of sale.
In the past, there have been some attempts to protect user""s of cellular phones from such radiation. However, none of those approaches has been entirely satisfactory. One such protective device for cellular telephone users is illustrated in the Katz U.S. Pat. No. 5,336,896. Here the entire cellular phone, including the antenna is placed in a shielding enclosure. The cell phone antenna is retracted into the shielding enclosure and makes contact with a second antenna outside the shielding enclosure. The second antenna is mounted on a tilt and swivel base so that it can be moved away from the user""s head to reduce exposure to the radiation emanating from it. Even if the energy level is somewhat reduced, the head of the user is still exposed directly to the radiation.
Another prior art patent is that of Schwanke, U.S. Pat. No. 5,657,386. This patent discloses a cellular phone having a shield for protecting the user from electromagnetic radiation emanating from the antenna. The shield is pivotally mounted to the housing of the cell phone and it can be positioned between the antenna and the head of the person using the telephone to protect the person from radiation emitted by the antenna. When the shield is in its protective position, it only shields that portion of the antenna extending upwardly outside of the cell phone housing. The portion of the antenna inside the cell phone housing does not have any of the shield structure blocking radiation emanating therefrom.
It is an object of the invention to provide a novel Radio Frequency Radiation (xe2x80x9cRFRxe2x80x9d) Shield Unit for protecting users of wireless telephones from harmful radiation.
It is also an object of the invention to provide a novel RFR Shield Unit that will slide down over the top end of existing wireless phones so that it will cover the bottom end of their antennas which are inside the housing of the wireless phones.
It is another object of the invention to provide a novel RFR Shield Unit fabricated of plastic material having carbon fibers embedded therein for absorbing and dispersing radiation.
It is a further object of the invention to provide a novel RFR Shield Unit that is easily and quickly installed or removed from existing wireless phones.
It is an additional object of the invention to provide a novel RFR Shield Unit for wireless telephones that is economical to manufacture and market.
It is also an object of the invention to provide a novel RFR Shield Unit that has a grounding member located on its outer surface where it can contact the ear or head of the person using the wireless telephone.
The Radio Frequency Radiation (xe2x80x9cRFRxe2x80x9d) Shield Unit for a wireless telephone has an upright oriented housing whose bottom end is open so that the top end of a wireless telephone may be received therein. The height of the chamber in the housing of the unit is such that the lower end of the housing extends downwardly over that portion of the antenna of the wireless phone that is located within the housing of the phone itself. An aperture is formed in the top end of the housing of the RFR Shield Unit that communicates with its chamber for allowing the antenna on the top end of a wireless telephone to extend out of the housing.
An antenna shield member extends upwardly from the top end of the housing and is located forwardly of the aperture in the housing so that it will intercept radiation that would be emitted from the antenna of a wireless telephone directed toward the head of the user of such a telephone. The rear surface of the antenna shield member has a concave surface that extends parallel to the antenna of the wireless phone and this concave surface receives and disperses the radiation from the antenna of the cell phone in an extremely effective manner. In one presently preferred embodiment, the housing and the antenna shield member are fabricated of a plastic material having carbon fibers embedded therein for absorbing and dispersing radiation. Also in the preferred embodiment, the RFR Shield Unit is formed from two members, a front cover member and a rear cover member. A plurality of membranes are positioned between the rear surface of the front cover member and the front surface of the rear antenna member for intercepting any radiation that passes through any of the apertures in the front wall of the front cover member. These membranes are made of carbon fiber material that has been cut into strips and tightly woven together. The combined structure of the membrane members and the carbon fiber impregnated plastic material structure of the RFR Shield Unit has been successful in blocking the transmission of better than 96% of the radio frequency radiation emanating from the antenna of a wireless phone. This is a remarkable achievement that is superior to anything presently in the marketplace.
A grounding member is located on the front surface of the housing and has prongs extending from its rear surface that seat right into the carbon fabric of the membranes positioned within the interior of the antenna shield member. The carbon fiber deflects much of the radio frequency radiation. Some of the RFR is absorbed by the carbon fiber and directed into a flow of electrons. These electrons then flow into the grounding member through its prongs. When the user of the wireless phone places it in contact with their ear or head, their body absorbs some of this harmless energy. In the preferred embodiment, the grounding member is made of brass and its outer surface is covered by a layer of gold. It provides excellent conductivity.